package com.jelly.common.util.http;

import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.io.OutputStreamWriter;
import java.net.HttpURLConnection;
import java.net.URL;

/**
 * @创建人 ql
 * @创建时间 2018-08-17 15:26
 * @功能描述: 请求工具类
 **/
public class HttpUtils {

    /**
     * 模拟post请求。
     */
    public static String sendPost(String url, String param) {
        String result = "";
        BufferedReader in = null;
        try {
            String urlNameString = url;
            URL realUrl = new URL(urlNameString);
            // 打开和URL之间的连接
            // URLConnection connection = realUrl.openConnection();
            HttpURLConnection connection = (HttpURLConnection) realUrl.openConnection();
            // 设置通用的请求属性
            connection.setDoOutput(true);
            connection.setDoInput(true);
            connection.setRequestMethod("POST");
            connection.setUseCaches(false);
            connection.setInstanceFollowRedirects(true);

            connection.setRequestProperty("accept", "*/*");
            connection.setRequestProperty("connection", "Keep-Alive");
            connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)");

            // 建立实际的连接
            connection.connect();

            OutputStreamWriter out = new OutputStreamWriter(connection.getOutputStream(), "UTF-8");
            out.write(param); // 向页面传递数据。post的关键所在！
            // DataOutputStream out = new DataOutputStream(connection.getOutputStream());
            // out.writeBytes(URLEncoder.encode(param,"UTF-8"));
            out.flush();
            out.close();

            // 获取所有响应头字段
            // Map<String, List<String>> map = connection.getHeaderFields();
            // 遍历所有的响应头字段
            /*
             * for (String key : map.keySet()) {
             * System.out.println(key + "--->" + map.get(key));
             * }
             */
            // 定义 BufferedReader输入流来读取URL的响应
            in = new BufferedReader(new InputStreamReader(connection.getInputStream(), "UTF-8"));
            String line = null;
            while ((line = in.readLine()) != null) {
                result += line;
            }
        } catch (Exception e) {
        }
        // 使用finally块来关闭输入流
        finally {
            try {
                if (in != null) {
                    in.close();
                }
            } catch (Exception e2) {
//                e2.printStackTrace();
            }
        }

        return result.toString();
    }

}
